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coondoggie writes "A radiation-proof Cisco router was sent into space today aboard an Intelsat satellite with the goal of setting up military communications from space. The router/satellite combo is a key part of the US Department of Defense's Internet Routing In Space (IRIS) project, which aims to route IP voice, video and data traffic between satellites in space in much the same way packets are moved on the ground, reducing delays, saving on capacity and offering greater network flexibility, Cisco stated."

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If slashdot blocks posts from 60.217.227.225, we'd be all set, unless these posts are being made with a proxy. If that's the case, how about blocking any posts with hrefs to coolforsale.com and flagging the UUID?

Because on wednesday the hrefs will point to wickedcooldeals.com, and on thursday they will point to supersalecooldeals.com, and on friday they will point to awesomedealsforsale.com, and on saturday...

I thought I read somewhere that lead is exactly the wrong thing to use if you're shielding against cosmic rays. While cosmic rays themselves are most likely to pass right through human bodies or sensitive electronics without "hitting" anything important. If you shield with lead, the cosmic rays do an excellent job busting alpha (or was it beta) radiation loose from the lead itself, which then wreaks havoc when those particles collide with humans or electronics in the surrounding environment.

Lead is not a good insulator for charged particles because rapidly decelerating particles create X-rays (braking radiation, I'd be damned if I remember how it's written in German). Of course, you can make thick enough lead blocks to adsorb the generated radiation, but It's much better to use insulation made of light chemical elements.

That's why, for example, Apollo spaceships used polyethylene and not lead foil for shielding.

"Factoring in other normal delays from network sources gives a typical one-way connection latency of 500–700 ms from the user to the ISP, or about 1,000–1,400 milliseconds latency for the total Round Trip Time (RTT) back to the user. "

Yeah, I thought that too, but it occurred to me that satellite-to-ground communication is limited by the ground stations within the footprint of the satellite. If the only available ground stations are saturated with other traffic, it may very well be that a space-routed signal arrives at its destination before a direct to ground routed signal under certain conditions.

The idea would not be for communication via satellite network to another ground station, that would likely be more effectively improved by u

I can generally tell when I'm on a long-distance voice call that uses sat relay rather than a terrestrial link. More episodes when both parties unintentionally talk over one another, followed by an awkward silence as each politely waits for the other to resume.

Look at the larger picture. Moving the "hub" and routing logic to the satellite could reduce the total number of satellite hops between nodes without having to rely on a TDMA network. Instead of two hops for two spokes to talk to each other, this could perform the routing logic at the satellite and route directly between the two spokes. "reduced latency" is from reducing the number of satellite hops. This will not reduce any latency for a single hop, obviously.

It is routing satellite to satellite communications. Currently, if you had to send a signal from location S to location R and they were each serviced by different satellites, you would have to send from S up to sat1 back down to an intermediate ground station (or two), back up to sat2 and then back down to location R. With this system, you send a signal up to sat1, across to sat2, then down to R.

Also, don't forget that this is for military communications. Having an untappable link that others cannot li

Not if your second leg did not have to go over the satellite. It would be a very poorly designed system if it did. Most current sat systems don't work this way. The downlink is some where centralized and accessible by other communication transports, like the Pentagon.

Satellites achieve "routing" by effectively circuit selection. If you want to talk to this part of the world, use this freq, other part another freq.

Putting a router in space that will be obsolete in 2 years just doesn't make any sense.

This could allow for two spokes on an FDMA system to route directly to each other without having to go through the central hub and two satellite hops. FDMA links are fixed frequencies back to to a hub, so normally for two spokes to talk to each other, you have to take two satellite hops and go through the hub. This should eliminate that.

Of course you could go TDMA, but the number of nodes you can have directly linked to each other via virtual circuits is limited. Again, moving the routing logic to the satel

You obviously haven't worked with Cisco VoIP over satellite links. It works perfectly fine over single satellite hops and up to three hops, in my experience. I've had VoIP calls with 2-3 second delays because of the number of hops and radio links that were completely functional. Of course there's delay. DoD users are far more tolerant of the delay than normal users, though. Usually it's as simple as using the word "over"...:)

I'm sure Cisco conveniently forgot to explain the concept of latency before they sold them voice service on and router in space.

Yes, latency being the problem it is, let's go back to half-duplex. In fact, let's go back to telegraphy. We should be able to do something with all that wire being displaced by all those wireless hot spots.

Back in the earlier days of the less popular Internet, I used to get a kick out of pining mcmurdo.gov , the US base in McMurdo Sound, Antarctica [google.com], because it was as far as I could reach on the Net (ping times usually about 800ms). Before I'd traveled very much around the physical globe, I'd stretch my imagination to the scale spanning "me to McMurdo".

Latency is a bitch. As someone who has worked closely with IP based satellite solutions the average latency to a geosynchronous satellite (ones that are over the same spot on the earth at all times) is about 80 ms each way, or 160ms round trip. To get data from a war zone, such as the middle east, over a wholly government controlled satellite network, back to the US would take at least two satellite hops for a total of at least 320ms in addition to any other equipment delay. This becomes even more proble

The summary is a bit misleading. Intelsat was launched around midnight Sunday night PST or, if you will, early Monday morning. Technically Intelsat was in space and correcting its orbit on Monday, not today, as the summary implies:

A radiation-proof Cisco router was sent into space today...

Just some early morning pedantry for my fellow space nerds out there. =)

The big issue this presents is that if the router stops working, doesn't renew the IP address or just won't connect then who is going to unplug it, wait a few seconds and plug it back in? Are they going to have to send astronauts up to do this every time that happens?

The way things are right now we can't communicate directly from Iraq for example to US over satellite due to satellite footprint being too small. So it would go something like this: Iraq >>> Sat1 >>> Kuwait >>> Sat2 >>> Germany >>> Sat3 >>> US (Probably Maryland Fort Meade or Belvoir or something).
Each >>> represents a satellite hop adding roughly 50 to 150ms delay. This is not counting in other delay added by other earth based equipment. This

A geo satellite can see about 1/3 of the earth's surface and so there are satellites that can directly connect Iraq and the USA in a single hop - like Telstar 12 [telesat.com] for example. The delay is what it is, but terrestrial networks that cover that distance are not exactly delay free either and a bummer to install in a war zone.

Once you hit Kuwait or Germany (leaving Iraq), you're hooked into terrestrial connectivity as a primary. So it's only a single satellite hop and then 300ms or so to travel to the states via fiber. If you're on a smaller FOB in Iraq that needs to hop to it's parent unit, then Kuwait or Germany, then you'll have two satellite hops.

The Sat-to-Sat link could be used instead of the fiber connectivity. While it may not save much latency, it could be a much larger and less congested pipe depending on the frequenci